The reaction of white phosphorus with aq. NaOH gives phosphine along with another phosphorus containing compound. the reaction type, the oxidation states of phosphorus in phosphine and the other product respectively are

The reaction of white phosphorus with aqueous alkali is P4+3NaOH+3H2O⟶PH3+NaH2PO2In the above reaction phosphorus is simultaneously oxidized.P4(O)⟶NaH2P+1O2 as well as reducedP4(O)⟶P-3H3Therefore, this is an example of disproportionation reaction. Oxidation number of phosphorus in PH3 is - 3 and in NaH2PO2 is + 1.However, + 1 oxidation number is not given in any option, one might think that NaH2PO2 has gone to further decomposition on heating. 2NaH2PO2⟶ΔNa2HPO4     +5+PH3